Perl Regex Repetition: Examples

a* zero or more a’s
a+ one or more a’s
a? zero or one a’s (i.e., optional a)
a{m} exactly m a’s
a{m,} at least m a’s
a{m,n} at least m but at most n a’s repetition? same as repetition but the shortest match is taken

Perl Regex Examples

s/foo/bar/;
replaces the first occurrence of the exact character sequence foo in the “current string” (in special variable $_) by the character sequence bar; for example, foolish bigfoot would become barlish bigfoot

s/foo/bar/g;
replaces any occurrence of the exact character sequence foo in the “current string” by the character sequence bar; for example, foolish bigfoot would become barlish bigbart

s/foo/bar/gi;
replaces any occurrence of foo case-insensitively in the “current string” by the character sequence bar (e.g. Foo and FOO get replaced by bar too)

About The Author

Dan Zimmerman is a writer at Shoutability. He has passion for all things marketing, programming and social media. He is a father and entrepreneur. Dan is a lifetime learner, and loves to spend time attending classes, webinars, and summits.